From owner-freebsd-hardware Fri Oct 18 10:17:48 1996 Return-Path: owner-hardware Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id KAA08884 for hardware-outgoing; Fri, 18 Oct 1996 10:17:48 -0700 (PDT) Received: from GndRsh.aac.dev.com (GndRsh.aac.dev.com [198.145.92.241]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id KAA08879 for ; Fri, 18 Oct 1996 10:17:45 -0700 (PDT) Received: (from rgrimes@localhost) by GndRsh.aac.dev.com (8.7.5/8.7.3) id KAA27086; Fri, 18 Oct 1996 10:17:19 -0700 (PDT) From: "Rodney W. Grimes" Message-Id: <199610181717.KAA27086@GndRsh.aac.dev.com> Subject: Re: collision count reported by netstat -I? In-Reply-To: <199610181607.JAA04414@saguaro.flyingfox.com> from Jim Shankland at "Oct 18, 96 09:07:38 am" To: jas@flyingfox.COM (Jim Shankland) Date: Fri, 18 Oct 1996 10:17:19 -0700 (PDT) Cc: hardware@freebsd.org X-Mailer: ELM [version 2.4ME+ PL25 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hardware@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > While investigating some network performance problems, I've noticed > that the collision count reported by netstat -I for SMC9332DST cards > running in 10 Mbit mode tends to be much higher than I would expect. > I do not believe I'm dealing with defective cards, as this happens > on multiple cards, and on networks that seem to be performing OK. > > As a specific example, a workstation with one of the SMC cards, > located on a moderately busy wire, reports about a 3.5% > collision rate (Opackets/Collisions). The principal router on > that wire (also a FreeBSD box), sporting a 3C509 card, reports a > collision rate of just under 1 in a *millino*. As it happens, > virtually all traffic to and from the workstation, plus quite a > bit more, passes through the router. > > Does anyone have any thoughts as to what might be the cause of this > huge difference? There appears to be a bug in the if_de.c driver that is reporting too many collisions. -- Rod Grimes rgrimes@gndrsh.aac.dev.com Accurate Automation, Inc. Reliable computers for FreeBSD